RU2723535C1 - Catheter pump with pump head for insertion into arterial blood system - Google Patents

Abstract

FIELD: medicine.SUBSTANCE: invention relates to medical equipment. Disclosed is a catheter pump with a pump head for insertion into an arterial blood system, with an external catheter placed in an external catheter with an internal catheter and rotatably mounted in the internal catheter by a rotary shaft for actuation of a pump head provided for expansion of the delivery element. Feeding element is installed with possibility of rotation between the distal support part and the proximal support part. Outer catheter on its distal end has a sleeve section surrounding the proximal support portion. Proximal support part for expansion of the feeding element is made with possibility of movement in axial direction relative to the sleeve section. Proximal support part includes a support receiving element, which has a rotary support part for rotary shaft rotationally connected to the distal end of the rotor shaft and an axially distal portion of force application for a portion of force application provided at the distal end of the internal catheter for axial movement of the proximal support portion relative to the sleeve portion.EFFECT: technical result is providing improved proximal support part for catheter pump.9 cl, 3 dwg

Description

The invention relates to a catheter pump with a pump head for insertion into the arterial circulatory (vascular) system, for example, into the aorta or heart, with an external catheter located in the external catheter by an internal catheter and rotatably disposed in an internal catheter by a rotor shaft to drive a pump head having the ability to expand the feeding element, the feeding element being mounted rotatably between the distal supporting part and the proximal supporting part, the outer catheter at its distal end having a sleeve portion surrounding the proximal supporting part, and wherein the proximal supporting part for expanding the feeding element with the possibility of movement in the axial direction relative to the sleeve section.

Catheter pumps of this type are known, for example, from EP 2,308,422 B1. As a rotating feed element, for example, a rotor with reclining impellers can be used, for example, as described in EP 768 900 B1. It is likewise possible that otherwise made feeding elements, such as spiral coils, can find application.

Catheter pumps are introduced as a temporary system of auxiliary circulation into the aorta of patients, in particular, when their own heart is not able to supply the body with sufficient oxygenated blood. Moreover, the feed element and the rotor shaft are driven with relatively high rotational speeds in the region from 7000 to 15000 rpm. The pump head of the catheter pump can remain in the aorta, in particular, after surgery for several days.

The basis of the present invention is the preferred improvement of the proximal support part mentioned at the beginning of the catheter pump.

This problem is solved by means of a catheter pump with the features of paragraph 1 of the claims. Thus, the invention provides that the proximal support portion, i.e. the supporting part, which in the axial direction is between the catheters and the other distal supporting part, includes a supporting receiving element, which has a rotating supporting part for rotatably connected rotational head rotationally rotationally connected to the distal end of the rotating head and an axially spaced apart part of the application of force for the provided at the distal end of the inner catheter of the force application portion for axially moving the proximal support portion relative to the sleeve portion. Due to the presence of such a support receiving element, which has a rotating support part and a part of the application of force, several functions can be implemented in one structural element in a very small structural space. On the one hand, the feeding element, and in particular the rotor of the feeding element, can be mounted with rotation lock in the rotating support part. On the other hand, due to the presence of a part of the application of force on the supporting receiving element, relative movement between the sleeve portion of the external catheter and the supporting receiving element for expanding the feeding element can functionally reliably occur.

In this case, the sleeve portion may be located entirely on the external catheter or be formed by it. In addition, it is possible that the sleeve section can be made as a separate structural element, which is rigidly connected to the external catheter.

To compress or fold the feed element, the sleeve portion is moved relative to the proximal support portion in the axial direction from the distal support portion.

Preferably, the support receiving element is sleeve-shaped. In this case, the rotating support part is formed by the first internal groove, and the part of the application of force by the second internal groove. In general, as a result of this, the relatively simple support receiving element formed can be formed by the rotating support part and the force application part. In this case, the first inner groove may have bevels made relatively flat, so that the rotating head can accordingly be optimally mounted. In this case, the second inner groove can be made, in particular, in such a way that the force-applied portion of the ring can be functionally reliably received by the second inner groove.

A particularly preferred embodiment of the invention provides that the support receiving element includes at least two support liners. That is, in the presence of two supporting inserts two half-inserts are used. The use of two or more support liners has the advantage that the installation of the proximal support part is possible in a simple manner.

For this, the sleeve section is preferably made in such a way that, for mounting the proximal support portion, first the support liners are radially mounted on the rotating head and the force application section, and then the sleeve section is axially shifted above the support liners. This has the advantage that other mounting or fixing means may fall away. Support liners are securely located in the sleeve section.

The support receiving element and, in particular, the supporting inserts may have recesses, preferably on the radial outer side facing the sleeve portion, so that flushing fluid flowing between the internal catheter and the external catheter can flow between the supporting receiving element, respectively, the supporting inserts, and the inner wall of the sleeve section. In this case, the recesses are formed in the support receiving element, respectively, of the support liners, preferably as grooves extending in the axial direction. As a result of this, it can be ensured that the flushing fluid that is transported between the external catheter and the internal catheter to the pump head can pass through the proximal support portion without the fluid having to pass through the rotating support portion.

In addition, according to the invention, it is possible that a pressure chamber is adjacent to the distal end of the support receiving element, in which the washing fluid is collected during operation and from which the washing fluid is directed further to the distal supporting part, into the aorta and / or back through the internal catheter. Thereby, it can be achieved that, on the one hand, even a distal support part is supplied with a corresponding flushing liquid. On the other hand, a portion of the flushing fluid, which may be in the volume of a third of the introduced flushing fluid, may be diverted past the rotating head through the rotating supporting portion back through the internal catheter. As a result of this, it can be achieved that even the rotating support part can be washed sufficiently and lubricated with a suitable flushing fluid. So, the flushing fluid passing through the rotating support part is guided back through the internal catheter, respectively, through the lumen between the internal catheter and the rotor shaft, so that the possible products of abrasion of the support, if possible, do not enter the patient's bloodstream.

The area of application of force is preferably located on the sleeve, which is rigidly located on the distal end of the internal catheter. In this case, the sleeve may surround the inner catheter in the radial direction. The site of application of force can be performed, in particular, as an annular collar extending in the radial direction, which engages in the second inner groove of the support receiving element. In this way, a combination of movement between the inner catheter, respectively, the sleeve and the supporting receiving element, respectively, of the supporting inserts, can be reliably acting in the axial direction.

The sleeve, for its part, on the side facing away from the rotating support part may have a shoulder portion remote from the force application portion. This shoulder portion can be used as an axial stop in the external catheter, respectively, a spacer sleeve provided between the sleeve and the external catheter.

Moreover, it is preferable if the spacer sleeve has radially extending recesses for passing the flushing fluid. As a result of this, it can be ensured that the flushing fluid that is transported between the catheter and the external catheter to the proximal support portion can be guided between the lower portion and the spacer sleeve even when the spacer sleeve comes in full contact with the shoulder portion.

Other details and preferred embodiments of the invention may be derived from the following description, on the basis of which an embodiment of the invention is described and explained. Shown:

Figure 1 is a perspective view of the pump head corresponding to the invention of a catheter pump with a partially cut proximal support part;

Figure 2 is a longitudinal section shown in figure 1 of the proximal support part, and

Figure 3 - shown in figure 2 of the supporting part before its installation.

The catheter pump 10 shown in FIG. 1 has a pump head 12 for insertion into the patient’s aorta or heart. The pump 10 includes an external catheter 14, an internal catheter 16, and a rotary shaft 18 rotatably disposed in the inner catheter 16. The rotary shaft 18 can be driven by the feeding (conveying) element 20 shown in FIG. 1 in the form of a rotor 42 with the impellers 22. In this case, the impellers 22 are located on the rotor 42 between the distal abutment site 24 and the proximal abutment site 26. The supply element 20, respectively, of the impellers 22 are surrounded by a cage 28, which includes various threads 30. In the expanded state, which is shown in FIG. 1, the cell 28 is convex, so that the impellers 22 inside the cell 28 can rotate freely. To introduce the pump head 12 into the aorta, the pump head 12 is not expanded, but is in a collapsed, respectively, folded state. In this folded state, the impellers 22 lie close to the axis of rotation of the rotor 42 and the threads 30 of the cage 28 are in a position parallel to the axis of rotation of the rotor 42.

As it becomes clear from the section according to figure 2, the proximal support portion 26 has a support receiving element 32, which includes a rotating support part 34, as well as part 36 of the application of force. In this case, the rotating support part 34, as well as the part 36 of the application of force, respectively, in the form of circumferential inner grooves are inserted into the sleeve-shaped support receiving element 32.

In the rotatable support portion 34, a rotatable head 40, preferably a spherical head, is rotationally connected rotatably connected to the distal end 38 of the rotor shaft 18 rotationally connected. By means of the rotating head 40, the rotor 42 with the impellers 22 is driven. The rotor shaft 18, for its part, is driven by its drive at its proximal end, not shown.

In the force application portion 36, a force application portion 46 is provided. Section 46 of the application of force is formed by an annular collar, which is provided on a sleeve 52 rigidly connected to the internal catheter 16. In this case, the annular collar enters with a geometrical closure into the force application portion 36 formed in the form of a circumferential inner groove.

The supporting receiving element 32, for its part, is placed in the sleeve portion 50 located on the distal end 48 of the outer catheter 14, which is movable in the axial direction relative to the supporting receiving element 32 and thereby relative to the inner catheter 16.

By the described arrangement, as a result of the axial movement of the outer catheter 14 relative to the inner catheter 16 and thereby the support receiving element 32 which is relatively movably compatible with the inner catheter 16, the sleeve portion 50 is displaced from the distal position shown in FIG. 2, in which the feeding element 20 extends to the right proximal position, whereby the impellers 22 fold and the cell 28 collapses.

In the distal position of the sleeve portion 50 shown in FIG. 2, adjacent to the distal end of the support receiving element 32, there is a pressure chamber 54. This chamber 54 is caused by the fact that the sleeve portion 50 moves axially in the distal direction when the feed member 20 expands. In the proximal position of the sleeve portion 50, that is, with the feed element 20 collapsed, the support receiving element 32 is located in the pressure chamber 54.

As it becomes clear from FIG. 3, the support receiving element 32 consists of two support liners 56. To mount the proximal support portion 26, first, both support liners 56 are radially mounted on the rotating head 40 and the force application portion 46. Subsequently, the sleeve portion 50 is axially displaced over the support shells 56. This has the advantage that the mounting, respectively, fixing of the support shells 56 can be carried out without other structural parts or fixing means. With this arrangement, the requirements for this support can be realized in a very small installation space.

The sleeve 52 on the side facing away from the rotating support portion 34 has a shoulder portion 68 spaced from the force applying portion 46. Moreover, the shoulder portion 68 together with the spacer sleeve 62 serve as an axial stop and thus limit the axial displacement path of the sleeve portion 50.

In addition, as it becomes clear from figure 3, the support liners 56 on their radially outer side have recesses 58 in the form of axially extending grooves. As a result of this, during operation of the catheter pump 10, the flushing fluid flowing between the inner catheter 15 and the outer catheter 14, which is indicated in FIG. 2 by arrow 60 and which passes by the spacer sleeve 62, can flow into the pressure chamber 54 between the support liners 56 and the inner wall of the sleeve section 50. The flushing fluid, which is pressurized between the inner catheter 16 and the outer catheter 14, is thereby collected in the pressure chamber 54, so that most of the flushing fluid does not come into contact with the rotating head 40 or the rotating supporting part 34. Then , from the pressure chamber 54, the flushing fluid through the corresponding recesses not shown in the figures, as indicated by arrows 64, can be transported to the distal support part 24 to supply the support part 24. Another part of the flushing fluid from the pressure chamber 54 through a rotational separation, which is also not indicated on figures may go out into the aorta at. The third part, approximately a third of the flushing fluid, from the pressure chamber 54, as indicated by arrows 66, can flow through the rotating support part 34 to flush and lubricate it, and can be diverted to the proximal end of the external catheter 14 between the internal catheter 16 and the rotor shaft 18. As a result This can be achieved by the fact that, on the one hand, the rotating head 40 and, on the other hand, the entire rotor shaft 18 is provided with sufficient flushing and lubrication, and the proportion of flushing fluid that flows through the support receiving element 32 does not enter the patient’s aorta.

The sleeve 52 on the side facing away from the rotating support part 43 has a shoulder portion 68 distanced from the force application portion 46. Together with the spacer sleeve 62, it can serve as an axial stop. Due to the fact that flushing fluid can freely pass between the sleeve 52 and the spacer sleeve 62, the spacer sleeve 62 has, as shown in FIG. 1, recesses 70 that remain open even when the spacer sleeve 62 is adjacent to the shoulder portion 68 of the sleeve 52 .

By means of the described construction of the proximal support portion 26, a simple and yet reliable operation of the installation of the support portion 26 with both support liners 56 can be carried out, and at the same time, the axial movement of the proximal support portion 26 relative to the sleeve portion 50 is provided to expand the feed member 20.

Claims (9)

1. A catheter pump (10) with a pump head (12) for insertion into the arterial circulatory system, with an external catheter (14) located in the external catheter (14) with an internal catheter (16) and rotatably located in the internal catheter (16) a rotor shaft (18) for actuating provided on the pump head (12), with the ability to expand the feed element (20), and the feed element (20) is mounted for rotation between the distal support part (24) and the proximal support part (26) moreover, the outer catheter (14) at its distal end has a sleeve portion (50) surrounding the proximal support portion, and wherein the proximal support portion (26) for expanding the feed member (20) is movable in the axial direction relative to the sleeve portion (50), characterized in that the proximal support part (26) includes a support receiving element (32), which has a rotating support part (34) for co the rotary head (40), which is not rotatably connected to the distal end (38) of the rotary shaft (18) and the force application axially spaced from it (36) for the force application section provided at the distal end (44) of the internal catheter (16) (46) for axial movement of the proximal support part (26) relative to the sleeve portion (50). 2. A catheter pump (10) according to claim 1, characterized in that the supporting receiving element (32) is made sleeve-like and the rotating supporting part (34) is formed by the first internal groove, and the part (36) of the application of force is the second internal groove. 3. A catheter pump (10) according to claim 1 or 2, characterized in that the supporting receiving element (32) includes at least two supporting inserts (56). 4. A catheter pump (10) according to claim 3, characterized in that the sleeve section (50) is made in such a way that, for mounting the proximal support part (26), first the support liners (56) are radially mounted on the rotating head (40) and to the force application portion (46), and then the sleeve portion (50) in the axial direction is displaced over the support liners (56). 5. The catheter pump (10) according to one of the preceding paragraphs, characterized in that the supporting receiving element (32) on the outer side facing the sleeve portion (50) has recesses (58) so that it flows between the internal catheter (16) and with an external catheter (14), the flushing fluid can flow between the support receiving element (32) and the inner wall of the sleeve portion (50). 6. A catheter pump (10) according to one of the preceding claims, characterized in that a pressure chamber (54) is adjacent to the distal end of the support receiving element (32), in which during operation the washing liquid is collected and from which the washing liquid is then directed to the distal supporting part (24), into the arterial circulatory system and / or back through an internal catheter (16). 7. The catheter pump (10) according to one of the preceding paragraphs, characterized in that the area (46) of the application of force is located on the sleeve (52), which is rigidly connected to the distal end of the internal catheter (16). 8. A catheter pump (10) according to claim 7, characterized in that the sleeve (52) on the side facing away from the rotating support part (34) has a shoulder portion (68) remote from the force application portion (46), which together with the spacer sleeve (62) forms an axial stop. 9. A catheter pump (10) according to claim 8, characterized in that the spacer sleeve (62) has radially extending recesses (70) for passing the flushing fluid.

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